Add setup func

Signed-off-by: Miek Gieben <miek@miek.nl>

plugin/torrent/README.md

+# torrent
+
+## Name
+
+*torrent* - use BitTorrent to disseminate zone data.
+
+## Description
+
+The *torrent* plugin uses the BitTorrent protocol to disseminate zone data. Multiple peers can
+connect and down- and upload the data. A couple of nodes can be `seed` only meaning they will update
+the torrent when their zone data changes. Non-`seed` peers will write received data back into the
+zonefile - once the torrent is fully downloaded.
+
+## Syntax
+
+The simplest syntax is for a peer wanting to receive the zone data:
+
+~~~ txt
+torrent DBFILE
+~~~
+
+*  **DBFILE** the zone database file to torrent. If the path is relative, the path from the
+   *root* plugin will be prepended to it.
+
+For peers seeding the torrent use this, slightly expanded, syntax
+
+~~~ txt
+torrent DBFILE {
+    seed
+}
+~~~
+
+* `seed` tells *torrent* to seed content from **DBFILE** to the peers, it will _never_ write to
+  **DBFILE**. When `seed` is _not_ specified **DBFILE** will be written to once the entire torrent
+  is downloaded.
+
+## Examples
+
+~~~ txt
+example.org {
+    file db.example.org
+    torrent db.example.org
+}
+~~~
+
+## Also See
+
+## Bugs

plugin/torrent/session.go

+package torrent
+
+import (
+	"log"
+	"time"
+
+	rtorrent "github.com/cenkalti/rain/torrent"
+)
+
+func (t *Torrent) StartSession() error {
+	s, err := rtorrent.NewSession(torrent.DefaultConfig)
+	if err != nil {
+		return err
+	}
+
+	// Add magnet link
+	tor, _ := ses.AddURI(magnetLink, nil)
+
+	// Watch the progress
+	for range time.Tick(time.Second) {
+		s := tor.Stats()
+		log.Printf("Status: %s, Downloaded: %d, Peers: %d", s.Status.String(), s.Bytes.Completed, s.Peers.Total)
+	}
+
+}

plugin/torrent/setup.go

+package torrent
+
+import (
+	"path/filepath"
+
+	"github.com/coredns/coredns/core/dnsserver"
+	"github.com/coredns/coredns/plugin"
+
+	"github.com/caddyserver/caddy"
+)
+
+func init() { plugin.Register("torrent", setup) }
+
+func setup(c *caddy.Controller) error {
+	tor, err := parse(c)
+	if err != nil {
+		return plugin.Error("sign", err)
+	}
+
+	c.OnStartup(func() error {
+		// go tor.do()
+		return nil
+	})
+	c.OnShutdown(func() error {
+		close(tor.stop)
+		return nil
+	})
+
+	// Don't call AddPlugin, *sign* is not a plugin.
+	return nil
+}
+
+func parse(c *caddy.Controller) (*Torrent, error) {
+	t := &Torrent{}
+	config := dnsserver.GetConfig(c)
+
+	for c.Next() {
+		if !c.NextArg() {
+			return nil, c.ArgErr()
+		}
+		dbfile := c.Val()
+		if !filepath.IsAbs(dbfile) && config.Root != "" {
+			dbfile = filepath.Join(config.Root, dbfile)
+		}
+		t.dbfile = dbfile
+
+		for c.NextBlock() {
+			switch c.Val() {
+			case "seed":
+				t.seed = true
+			default:
+				return nil, c.Errf("unknown property '%s'", c.Val())
+			}
+		}
+	}
+
+	return t, nil
+}

plugin/torrent/setup_test.go

+package torrent
+
+import (
+	"testing"
+
+	"github.com/caddyserver/caddy"
+)
+
+func TestParse(t *testing.T) {
+	tests := []struct {
+		input     string
+		shouldErr bool
+		exp       *Torrent
+	}{
+		{`torrent testdata/db.miek.nl {
+			seed
+		 }`,
+			false,
+			&Torrent{dbfile: "testdata/db.miek.nl", seed: true},
+		},
+		{`torrent testdata/db.miek.nl`,
+			false,
+			&Torrent{dbfile: "testdata/db.miek.nl"},
+		},
+		// errors
+		{`torrent db.example.org {
+			bla
+		 }`,
+			true,
+			nil,
+		},
+	}
+	for i, tc := range tests {
+		c := caddy.NewTestController("dns", tc.input)
+		tor, err := parse(c)
+
+		if err == nil && tc.shouldErr {
+			t.Fatalf("Test %d expected errors, but got no error", i)
+		}
+		if err != nil && !tc.shouldErr {
+			t.Fatalf("Test %d expected no errors, but got '%v'", i, err)
+		}
+		if tc.shouldErr {
+			continue
+		}
+		if x := tor.dbfile; x != tc.exp.dbfile {
+			t.Errorf("Test %d expected %s as dbfile, got %s", i, tc.exp.dbfile, x)
+		}
+		if x := tor.seed; x != tc.exp.seed {
+			t.Errorf("Test %d expected %T as seed, got %T", i, tc.exp.seed, x)
+		}
+	}
+}

plugin/torrent/torrent.go

+package torrent
+
+// Torrent contains the file data that needs to be torrented.
+type Torrent struct {
+	dbfile string
+	seed   bool
+
+	stop chan struct{}
+}